Source : Webster's Revised Unabridged Dictionary (1913)

Armor \Ar"mor\, n. [OE. armure, fr. F. armure, OF. armeure, fr.
   L. armatura. See {Armature}.] [Spelt also {armour}.]
   1. Defensive arms for the body; any clothing or covering worn
      to protect one's person in battle.

   Note: In English statues, armor is used for the whole
         apparatus of war, including offensive as well as
         defensive arms. The statues of armor directed what arms
         every man should provide.

   2. Steel or iron covering, whether of ships or forts,
      protecting them from the fire of artillery.

   {Coat armor}, the escutcheon of a person or family, with its
      several charges and other furniture, as mantling, crest,
      supporters, motto, etc.

   {Submarine}, a water-tight dress or covering for a diver. See
      under {Submarine}.

Source : WordNet®

armour
     n 1: a military unit consisting of armored fighting vehicles
          [syn: {armor}]
     2: protective covering made of metal and used in combat [syn: {armor}]
     3: tough more-or-less rigid protective covering of an animal or
        plant [syn: {armor}]

armour
     v : equip with armor [syn: {armor}]